Accumulation and passive sampling of bisphenol analogues using triolein-embedded cellulose acetate membrane in waters

Abstract

Bisphenol analogues (BPs) are emerging contaminants that have been widely detected in water environments. The presence of substituted hydrophilic and hydrophobic groups in the molecule may lead to unclear performance in passive sampling. This study tested the accumulation capacity and passive sampling of fifteen BPs in a triolein-embedded cellulose acetate membrane (TECAM) passive sampler. In a dynamic accumulation experiment, twelve hydrophobic BPs accumulated in the TECAM with concentrations ranging from 251 ng g−1 to 6283 ng g−1, and three hydrophilic BPs did not accumulate during the 72 h exposure duration. BPs accumulations were determined by the hydrophilic and hydrophobic substituent groups in molecule structures. The estimated passive sampling parameters showed correlations to both the log Kow values and chemical structures, and compared to other contaminants, such as organophosphorus flame retardants. Environmental factors, including flow rate, temperature, salinity, and pH, that affect the accumulation of BPs in the TECAM were tested, and the flow rate was found to be an important factor affecting the uptake rate. The isotropic exchange kinetics for BPs in the TECAM were verified, and the results indicated that BPs can be calibrated with performance reference compounds (PRCs) in field applications. Finally, a field deployment of TECAM in river waters successfully estimated the time-weighted concentrations of two hydrophobic BPs. To address the inherent weaknesses of TECAM in sampling hydrophilic and moderately hydrophobic BPs, future studies should explore alternative passive samplers, such as hydrophilic-lipophilic balance sorbent-embedded cellulose acetate membranes, to sample BPs in surface waters.